Grind it, or not?

I have a stock '70 intake manifold pulled from a Buick Electra. I have removed the carburetor and I noticed that right under every bore of the manifold there is a lump. Do I have to grind those lumps or do they diffuse the air/fuel mixture a bit?

Thanks,

Bram

 

unless your building a 6000 rpm+ moter dont worry about them.

 

Thanks Kelly!